The present invention relates to a vacuum cleaner tube shaft having an upper tube part and a lower tube part that are turnably connected to one another, wherein each tube part has two tube sections that are inclined with respect to one another, the lower tube part has an end section supporting a nozzle that includes a nozzle part and a connecting part, the connecting part being connected to the end section while the upper end of the upper tube part is connected to a hose, a tube handle or the like.
Tube shafts of different types are previously known. The simplest tube shafts have one or more hollow, straight sections to which a tube handle with a hose and a nozzle is connected. The hose is further connected to a vacuum source arranged in a vacuum cleaner housing or to a suction port for a so-called central vacuum system.
A problem when using such tube shafts is that it is difficult to reach sufficiently far beneath low furniture and other details. Thus, the operator is forced to bend in order to decrease the angle between the tube shaft and the floor surface. This is, of course, uncomfortable and cumbersome.
In order to reduce this problem it has previously been suggested, see WO 89/07412, to use a flexible hose between two sections of the tube shaft, with a lower section of the tube shaft being adjustable to a position parallel to the floor surface. However, this arrangement is very primitive and it is difficult to operate the tube shaft in its normal position because of the flexibility of the hose.
A similar arrangement, but with additional elements to stabilize the two sections with respect to one another is also previously known, see SE 9600650. This arrangement is, however, very complicated because the existence of several ball joints, telescopically arranged components, and additional tube sections.
It is also previously known, see JP 725653, to manufacture the complete tube shaft, or a portion thereof, is made from flexible material, which means that the tube shaft is bent under the influence of the contact forces with the furniture. Even if such a design is appealing in the abstract, it is difficult to find material compositions that simultaneously provide the necessary flexibility and stability during normal use.
Moreover, U.S. Pat. No. 1,012,195 and U.S. Pat. No. 1,104,148 describe other types of arrangements for facilitating cleaning operations below furniture. U.S. Pat. No. 1,012,195 describes a tube shaft comprising two parts, a lower straight part and an upper handle part having a short air inlet section which is inclined with respect to an elongated air outlet section. When cleaning below furniture the upper part is turned 180.degree.. This, however, means that the handle part has to be moved to a position near the floor which is as uncomfortable as when using ordinary tube shafts. U.S. Pat. No. 1,104,148 describes an arrangement having a bent tube shaft that can be turned 90.degree. at each side of a central upraised position. However, when turning the tube shaft to one of its side positions the operator is forced to move the handle part towards the floor in order to reach under furniture. Consequently this arrangement has the same disadvantages as the arrangement described in U.S. Pat. No. 1,012,195.